The invention relates to appliances in general, and more particularly to improvements in appliances which process or consume water, particularly tap water. Still more particularly, the invention relates to improvements in electrical appliances which are provided with water softening facilities.
Commonly owned copending patent application Ser. No. 239,192 discloses an electric coffee making machine which heats tap water and wherein a stream of water is softened on its way from the container for a body of fresh tap water toward an electric heater prior to coming in contact with a supply of flavoring agent, such as comminuted coffee beans. This prevents the development of scale in the pipes, conduits and like parts of the appliance. The color of softening agent changes when its water softening capacity is reduced or exhausted, and the appliance is provided with means for permitting observation of the supply of softening agent so that the change of color can be detected for the purpose of replacing the partially or fully exhausted supply with a fresh supply of softening agent. The supply of softening agent can be installed in such a way that it can be observed and its color ascertained while in the operative position and/or that it is readily removable from the appliance in order to permit observation of its color.
Commonly owned copending patent application Ser. No. 239,211 discloses an electric steam iron wherein the stream of tap water which is to be heated and converted into steam is softened as a result of contact with a supply of softening agent. The softening agent is observable in the housing of the steam iron or upon removal from the housing in order to permit observation of its color. This enables the person in charge to replace the supply of softening agent when the color of the softening agent indicates that its water softening capacity is reduced or exhausted.
The just described appliances operate quite satisfactorily and the detection of the color of a supply of softening agent can be ascertained by the simple expedient of observing the supply in the appliance, by exposing the partially or fully concealed supply or by removing the supply from the appliance. However, there is no automatic indication or warning that the supply of softening agent should or must be replaced because it is no longer effective or because it is no longer capable of satisfactorily softening the stream or streams of water which are conveyed to a water heater or to another water processing or consuming component of the appliance.